Protective covering and method of processing same



. l Qct. 31, 1933. c FORD AL 1,932,617

PROTECTIVE COVERING AND METHOD OF PROCESSING SAME Filed Aug. 7, 1930 ATTORNEYS Fatented (Diet. 3i,

I Joseph C. Ford and Einar Olson, n, Wis.

Application August 7, 1930. Serial No. 473,717

I or ii a 18 Claims.

The present invention relates to cellulose products and to a method of producing and processing the same.

The invention has been developed more particularly in connection with the production and preparation for shipment and storage of a protective cap for use on bottles and the like, and for the purposes of illustrating the principles of the invention such an embodiment will be more par- 1 ticularly described. I

Protective caps of the type to be described as illustrating one embodiment of the invention are commonly preformed to conform more or less to the shape of the bottle, can, jar or other articles to which they are to be applied and are of such character that when applied and allowed to dry they shrink to conform closely to the engaged surfaces.

The present invention provides an improved 20 opaque cellulose material having in its final con= dition an opaque and glossy appearance and an improved method of processing cellulose material, whether opaque or not, whereby articles made therefrom and in what is, in fact, an inter mediate condition can be reduced to a substan= tially dry condition for shipment and storage and thereafter re-conditioned for use and for shrinking to final condition.

It is one of the features of the invention that articles such as bottle coverings made of cellulose when made opaque by the incorporation of finely divided opaque material and processed in accordance with the invention will retain their opaque and other desirable qualities.

The nature and objects of the invention will more clearly appear upon consideration of the description of a particular illustrative embodiment for the purposes of which description refer ence should be had to the accompanying drawing forming a part hereof and in which- Figure 1 is a view partly in elevation and partly in section showing a bottle cap constructed in accordance with the invention, and g Fig. 2 is a perspective of a similar cap prepared for shipment or storage.

The cap 5 shown, in the drawing and to be described for the purposes of illustration consists of a film of cellulose which has been pre-formed and while wet has been applied to a bottle 6 and dried. During the drying the cellulose film shrinks until it contracts tightly about the bottle.

The cap shown may be formed by precipitation or regeneration from a solution of cellulose such as viscose. The cellulose film may be rendered 5 opaque by the incorporation therein of finely divided opaque material. Conveniently this mate rialmay be introduced by chemical precipitation after the film is formed as above indicated. Sui phur can be chemically precipitated in the cellulose film in a manner to produce in the finally dried film not only the desired opacity but a glossy finish as well. The sulphur is precipitated in the form of milk of sulphur and is distributed throughout the film in such finely divided condition that a uniform opacity is efiected.

Sulphur may be precipitated from solutions of sulphur compounds in many different ways, of which the following are a few examples of the method used in connection with caps formed of a film ofcellulose. It can, for instance, be precipitated by,the action of an acid on a solution of sodium polysulfide, according to the following formula:

Sulphur can also be precipitated by the action of acid on a solution of sodium thiosuliate, accor to the following formula:

or, if an acid is added to a solution containing two molecules of sodium sulfide (News) for every molecule of sodium sulfite (NarSOr) sulphur will be precipitated without the evolution of H28 according to the following formula:

2NazS+NazSOa+3HzSO4=3NmSO4+3Eh0+3$ In practice a comb nation of the above methods Gil iii

till

' is used. Sodium polysulfide is formed by dissolv ing sulphur into a solution of sodium sulfide. To this sodium polysulfide is added sodium suliite' and sulphur is then-precipitated by the addition of sulphuric acid. The following procedure has been found to be most satisfactory. The caps are soaked in a solution containing sodium polysul= fide and sodium sulfite in the following propor= tions:

llario Sodium powered ZiutitfiEiiiIIIII: 2 Sodium sulfite ill Water d0 I The above solution is heated until all the sul-= phur has dissolved. Then, the film of cellulose in the form of a cap which is to be made opaque is immersed in this solution for from it to to minutes, depending upon the temperature. The caps are then removed and the film adhering to the surface removed as much as possible without ti solute the The uet is then immersed 11.1 a 5 to 10% sulphuric acid solution and allowed to remain there for a few minutes. The caps are then removed and washed in running water to remove the acid and reaction products. The sulphur is prec pitated in the in a highly colloidal form. The films in this condition are opaque and white and may be dyed to any desired color by well known dyeing. methods.

As a variation method, solutions of sulphur QGLTlpOLlIldS can be added to the viscose at any between the mixing and the coagulation. Title sulphur will then be precipitated coincidentally with regeneration oi the cellulose by acid, as described above.

Solutions oi sulphur compounds may also be added the fillfl'l by immersing the film in a sul= piiur compound bath prior to regeneration but or coincidentally with coagulation or formoi the film from the viscose solution By the is coagulation and regeneration is meant well known process of coagulation or preorecipitated kanthate. Th s may be accom plished. in one or more than one bath according to rectory practice.

lif, following the precipitation of sulphur, the is then dehydrated within a few hours, the sulphur remains in this highly colloidal form in the film. l oowever, the film is allowed to remain in water, the sulphur will change from a l glily dispersed or almost colloidal state at the time of precipitation to particles of larger size and the sulphur crystals increase in size, the SZCOUflfl. opaque eiiect of tlie is diminished, t. in condition might be reached where the of cellulose would again become traus in. substance. however, shortly after precipitating the sul-= the is washed free or" acid and reaction ducts and then dried, the sulphur will remain "be same highly dispersed form as it was when t precipitated. Upon drying, however, a film hydrated cellulose in any form will shrink very considerably by the loss of water and it is necessary thattlois shrinking be prevented in bot tle caps up to the time when they are to be ap-- plied to the bottles. It may be a matter of weeks or months before they are applied to bottles and yet it is iiriportant that the precipitated. sulphur be retained in its highly dispersed form. This be done by soaking the caps in solution of glycerirle containing a rlimum of do glycerine solution. Then, upon extraction oi the water, the glycerine remaining in the dim prevents the from shrinking and they remain soft and lit has further been found that the g retained by as film upon the removal of the water no effect upon the stability of the sulphur. The caps, then, in this form coritairiirig glycerne and in which sulphur has been precipitated as above, are ready for shipment.

d in amount of water equivalent to about Wu. times the it or the caps. Such soaksmall amount of glycerine remaining in the fi m is just sufficient to keep the film pliable without interferring with the shrinking.

The process outlined above is not restrictedto only bottle caps, but can of course be used to make opaque cellulose films in other forms than bottle caps, as, for example, sheet cellulose, thread cellulose, tubular cellulose or any other form.

In films in which, in the dry or dehydrated form, the retention of shrinking qualities is not of prime importance, the soaking in the high percent glycerine solution may be omitted and the film may instead be soaked in a low percent glycerine solution and then dehydrated, the small amount of glycerine acting only to keep the film soft and pliable and not appreciably retarding the shrinkage.

The foregoing particular description is illustrative merely and is not intended as defining the limits of the invention.

We claim:--

1. A shrinkable protective covering preserved for shipment and storage in substantially dry condition and adapted to be applied to and shrunk on a bottle or the like to ailord a protective covering comprising a pro-formed cellulose film saturated with a row, solution of glycerine in water and dried.

2. A protective covering for bottles, and the like, comprising a shrinkable film of cellulose adapted to be applied to a bottle, or the like, and when applied to shrink, said film comprising a substantial quantity of glycerine capable of maintaining said film flexible and causing it to retain its capacity for re-shrinking after being soaked in water said glycerine corresponding to at least the amount which said film would absorb when soaked in a solution containing 40% glycerine in water.

3. A film of the character described consisting of a cellulose compound made opaque and white by a substantial proportion of free sulphur distributed therein by precipitation.

s. A protective covering comprising a preformed cap impregnated with milk of sulphur and having the property of shrinking to form a glossy white opaque covering when applied to an article and shrunk thereon.

5. A film oi the character described consisting of a cellulose compound rendered opaque by an opaque substance distributed therein by precipitatiori.

6. A dry pre=formed protective covering for bottles, jars and the like comprising a shrinkable film having incorporated therein finely divided sulphur making said film opaque and glycerine as a preservative in a sufficient quantity to inhibit substantial shrinkage, said film having the capacity of being reconditioned by soaking'in water to remove glycerlne and thereafter shrinking to form a glossy opaque covering.

i. The method of producing a shrinkable protective covering for a bottle, jar or the like which comprises forming a cellulose film cap, impreghating said cap with a solution containing 40% of glycerine in water to maintain the flexibility of the cap and to prevent permanent shrinking when drying and, drying out the major portion of the water.

8. The method of forming and applying a protective covering to a bottle, jar or the like which comprises producing a -ore-formed cellulose film, I impregnating. said film with sulphur or the like by chemical precipitation, impregnating said film with glycerine as a preservative for shipment and s orage, removing a portion of said glycerine, and 150 i seam"? one to and it on a bottle, @l? the like.

The method of producing a white opaque shrinkable protective covering fora bottle, jar or the like which comprises regenerating a transparent cellulose film from a solution of cellulose such esviscose and precipitating finely divided sulphur in said film to make it-opaque and white.

no. lhe method of producing a white opaque glossy shrinkable protective covering for a bottle, jar or the like which comprises regenerating a cellulose n from a solution of cellulose and precipitating therein free sulphur during the regenerating process to form a white opaque glossy film.

shrinlrehle protective covering preserved filer shipment and storage in substantially dry condition and adapted to be applied to and shrunk on a bottle or the like to afford a protective coverhig comprising a preformed cellulose film with a 443% solution of glycerine in water and dried 12. A. protective cove for bottles, and the we, comprising a film of cellulose adapted to he applied to a bottle, or the like, and applied to said film comprising a sulostmtial quantity of glycerine capable of mainseiol flexible and causing it to rethin its capacity for re-shrinking after being soaked in. Water, said glycerine corresponding substantially to the amount which said film would absorb when soaked in a solution containing 40% glycerine in water.

e method of providing a protective covering for a hottle, jar orthe like which comprises for a cellulose iihn cap, impregnating said cap with solution containing 40% glycerine in water to maintain the fiexihilty of the cap and drying out the major portion of the water to facilitate storage of the cap, thereafter removing portion of the glycerinc and app said cap to a bottle, jar or the like and drying the cap to shrink it on the bottle, Jar or the like.

14. The method of forming and applying a protective covering to a bottle, jar or the like which comprises producing a pre-tormed cellulose film, impregnating said film with sulphur or the like by chemical precipitation, impregnating said film with a 40% solution of glycerine in water and drying out the water to preserve the film for shipment and storage, removing a portion of said glycerine by soaking in water, and applying said cap to and shrinking it on a bottle, jar or the like.

15. The method of producing a shrinkable protecting cover for a bottle, jar or the like, which comprises forming a film .cap from viscose, impregnating said cap with a solution containing at least 40% of glycerine in water to prevent permanent shrinking when drying, drying out the major portion of the water to form a dry cap capable of being reconditionedby soaking in water and capable thereafter of being permanently shrunk and dried.

16. The method of preserving shrinkable viscose material in condition to permit a future wetting and shrinking thereof which comprises saturating the viscose material with a solution con-' taining 40% glycerine in water and drying out the water.

1'7. The method of producing a white opaque glossy protective film which comprises regenerating a transparent film from viscose solution and precipitating finely divided sulphur in said film by soaking the film in a solution containing sodium sulfide and sodium sulfite and then immersing the film in a 5 to sulphuric acid solution and drying.

18. A. film of the character described consisting of a cellulose compound rendered opaque and glossy by precipitation therein 01' a substantial proportion of sulphur.

JOSEPH C. FORD. EINAR OLSON. 

